ES2276226T3 - AGENT FOR LEATHER HYDROFUGO PARESTO. - Google Patents

Abstract

Copolymer (I) (obtained from monomer units comprising one or more phosphorus containing compounds (a); and one or more linear or branched simply ethylenic unsaturated compounds (b) with 2-8C with additional at least two carbonic acid-, ester- or amide-groups or at least one anhydride group) is new. Copolymer (I) (obtained from monomer units comprising one or more phosphorus containing compounds (a) of formula R1O-P[(=O)(-OR2)]-OH; and one or more linear or branched simply ethylenic unsaturated compounds (b) with 2-8C with additional at least two carbonic acid-, ester- or amide-groups or at least one anhydride group) is new. R2ethylenic unsaturated 8-30C (preferably 18-22C) fatty alcohol; and R1H or R2. Independent claims are also included for: (1) the preparation of (I); (2) a medium (II), for hydrophobic treatment of leather, comprising (A); and (3) a method for treating leather comprising the use of (II) in at least one step.

Description

Agent for the waterproofing of leather.

The present invention relates to copolymers containing mono- and / or di-esters of phosphoric acid; to a procedure for its preparation; to an agent for the treatment of leather containing that copolymer, as well as to a procedure for the treatment of leather by using the agent for treating leather before
mentioned.

For most types of leather, whether they are shoe shovels or clothing leather, but also in leather and automobile upholstery leathers, a water-repellent sizing is increasingly required to generate water-repellent properties and simultaneously guarantee the perspiration. Such a water-repellent sizing can also be interesting, among other purposes, to achieve a stain repellent, for example in leather for upholstery of furniture and automobiles. Numerous agents and procedures applied for this purpose are known from the state of the art, in which the fundamentals are described by Hollstein, Bibliothek des Leders , volume 4, Entfetten, Fetten und Hydrofobieren bei der Lederherstellung , Umschau editorial, Frankfurt / Main 1987 and by Heldemann, Fundamentals of Leather Manufacturing , editorial E. Roether, Darmstadt 1993. In this regard, water-repellent substances are generally introduced into the fibrous structure of the leather, in particular in the empty spaces that, originally in living skin, were filled with tissue fluids. Since, usually, the hydrophobic substances used for it also have lubricating properties simultaneously, not only leather is provided with hydrophobic properties but at the same time it becomes flexible and gets a touch
nice.

Although in the state of the art it they know various water repellent substances and waterproofing, numerous investigations continue in this direction to continue optimizing waterproofing. Generally, most of the waterproofing agents known can be classified into two groups, resulting from different applications: waterproofing agents that are applied in organic phase and those who find application in phase watery Solvent waterproofing systems contain, for example, silicone oils or resins fluorocarbons and often cause resistance to improved water, but they have the disadvantage that they remain well solvent residues in the leather or must be disposed of expensive, and additionally they can cause problems in the process of waterproofing In addition, usually waterproofing takes place only superficially, which makes the subsequent difficult dyeing and finishing the leather and impairs the sensation to the touch of the leather.

For waterproofing in aqueous systems for example, long chain hydrocarbons, oils, greases, waxes, polymers or also silicones that, in part, can Be organically modified. However, to make possible the process in an aqueous bath, these hydrophobic substances must Emulsify first with emulsifiers that should not prevent waterproofing However, in this sense, it must have note that emulsifiers can also penetrate the fibrous structure of the leather. Therefore, they should be used emulsifiers for which this does not happen or those whose deposit In leather it does not lead to a worsening of its properties. For make waterproofing possible It is also necessary to be able to easily remove the properties hydrophilic emulsifiers.

As emulsifiers are considered, on the one hand, compounds containing carboxyl groups, such as soaps, sarcosinates or sulphosuccinates and, on the other hand, phosphates of alkyl, which can be added in addition to the system. These agents form insoluble compounds that eliminate the effect emulsifier with polyfunctional salts, such as salts of chrome (III) or aluminum, which are also used for tanning and, therefore, do not exert any disadvantageous effect on the leather. For example, document DE 3529869 A1 describes a procedure for waterproofing leather and skins in phase aqueous with a silicone oil and the salt of an N- (acyl C 9 -C 20) - amino acid as emulsifier In document DE 4115062 A1 the waterproofing leather and skins with a silicone and an acid alkylpolyalkyl ether carboxylic acid and / or an acid alkylarylpolyalkyl ether carboxylic as emulsifier.

In addition, hydrophobic substances used for waterproofing can also have an emulsifying effect, for example, by containing carboxylate or phosphate groups. DE 3800629 A1 describes, for example, a waterproofing process by using a polysiloxane containing carboxyl groups, in which the carboxyl groups, in the form of salts, themselves have emulsifying properties in water, while in the Non-neutralized form are suitable for waterproofing. Such polysiloxanes incorporating carboxylic acid groups or carboxylic acid anhydride groups are also described in EP 1087021 B1 in relation to other water-repellent substances. DE 19959949 A1 and EP 0745141 B1 describe similar silicones containing carboxyl groups, the properties of which can be further optimized by varying the binding element between the polyorganosiloxane chain and the carboxy group.
the.

In addition, in recent years they have developed numerous agents for the treatment of leather, for dyeing, compacted, greased and waterproofed hides and skins in aqueous solution, based on copolymers. These copolymers consist of hydrophilic and hydrophobic monomer components in different quantitative proportions The hydrophilic part of the copolymer causes the emulsion in water, the hydrophobic part generates, between others, the greasing and water-repellent effect of the copolymer. So by example, DE 2629748 A1 describes the use of copolymers from monoolefins with a chain length of approximately C 10 -C 30 and anhydride Maleic Similarly, from DE 3926167 A1 a known copolymer from similar monomer units. At DE 3909614 A1 are used for waterproofing copolymers from maleic anhydride and fatty acids unsaturated and / or its derivatives, which simultaneously contain the less a sulphonic group or sulfate in the molecule. Also these compounds, due to the carboxyl groups present in the molecule, they are practically self-emulsifying, but can be fixed with salts polyfunctional metal.

Also, phosphoric acid esters Specials, without other additives, can show a good effect Water repellent after the corresponding fixation. Such agents of greasing and waterproofing are known, for example, by the DE 3207562 A1. In this regard up to 10 units of phosphoric acid esters, which contain chain compounds long, unsaturated or saturated, as esterification components, they are linked together through diolic or polyol units. Leathers treated with such compounds are characterized by their softness, softness and a pleasant touch, as well as for a extraordinarily high dynamic water resistance.

In addition, DE 19942681 A1 describes a copolymer for the treatment of leather and skins that is obtained by polymerization of a mono- or acid di-carboxylic having a double bond carbon-carbon with a compound, whose compound can be prepared so that

a) a fatty alcohol and / or a wax alcohol with a dicarboxylic acid that has a double carbon-carbon bond or an anhydride thereof,

b) the product of step a) reacts with a alkanolamine and

c) the product of step b) is reacted with a phosphating agent. A treatment of leather and / or skins with such copolymers it gives them a soft, warm and silky touch. In addition, it has been shown that the aforementioned copolymers are Extremely resistant to washing and cleaning.

Agents and procedures above mentioned have been optimized to such an extent that for leather chrome plating can achieve excellent waterproofing, with Maeser values partially above 100,000 push-ups. A great progress has meant here in particular the use or co-use of modified silicones organically, for example silicones with carboxyl groups, which combine the good hydrophobic effect of silicone with the possibility of irreversible binding to chrome leather.

However, difficulties are always expected when too many additives are used in leather preparation hydrophilic This is for example the case for chrome leathers Intensively treated with vegetable and / or synthetic retannants, or for completely chrome-free leathers (FOC). High amount of hydrophilic functional groups of tanners Vegetable or synthetic causes a waterproofing in these leather types with agents known so far be Insufficient or even impossible.

Another unresolved problem is presented in the hydrophobic sizing of leather types called hard. For this leathers are understood that have only a limited softness, but on the contrary a greater thickness and high resistances These types of leather are mainly used for sturdy footwear, military and fire boots, footwear job protector, etc.

However, all agents of waterproofing described above cause a clear softness increase, since the hydrophobic hydrocarbons of long chain and, in particular also silicone oils, they have an excellent sliding effect, thereby reducing Intense friction between the leather fibers. Also they alkyl phosphates used for waterproofing and copolymers from maleic anhydride and hydrocarbons Long chain unsaturated lead to too soft leathers.

For the waterproofing of leathers in whose preparation many hydrophilic additives have been used, or in hard leathers, fluorocarbons have so far been used as waterproofing agents, which however are very expensive, or the addition of other additives has been necessary, such as tanning example, to counteract the
softness.

Therefore, the objective of the present invention was to find an agent that, on the one hand, provide a sufficient waterproofing in leathers treated intensely with hydrophilic additives, in particular vegetable tanning agents and / or synthetic, and allowed in the case of leather preparation chromium-free at least a reduced water absorption, but for another part had little or no influence on the softness, so that also suitable, in particular, for waterproofing of hard leather.

The objective was achieved by providing a copolymer that can be obtained from monomer units that understand

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a) one or more compounds of formula

one

where R_ {1} represents H or a mono- or poly-unsaturated fatty alcohol ethylenically with 8 to 30 carbon atoms and R2 represents the same or another mono- or polyunsaturated fatty alcohol ethylenically with 10 to 22 carbon atoms, Y

b) one or more linear chain compounds or branched, at least ethylenically monounsaturated, comprising 2 to 8 carbon atoms, and additionally, at least two groups carboxylic acid, ester or amide, or at least one anhydride group.

Phosphoric acid esters included in a) they preferably result from the reaction of phosphorus pentoxide with a fatty alcohol, resulting in a mixture of mono- and di-esters. However, phosphoric acid esters can also prepare in another known manner in the state of technique. For the formation of the copolymer it is possible to use both a monoester of pure phosphoric acid as an acid diester pure phosphoric, or also a mixture of an acid monoester phosphoric and a diester of phosphoric acid.

In this regard, residues R 1 and R 2 in the phosphoric acid diester can be both identical and different from each other. In addition, for the formation of the copolymer, such as monomer unit a) a mixture of two or more may be used monoesters of phosphoric acid with different R2, a mixture of two or more phosphoric acid diesters, in which, although in each compound R1 = R2, this remainder is different in both or more corresponding diesters, or a mixture of two or more phosphoric acid diesters in which R1 is different from R 2, and R 1 or R 2, or both, are different in both or more corresponding compounds. Preferably a mixture of a phosphoric acid monoester and an acid diester phosphoric, in which diester R 1 = R 2.

Mono- or fatty alcohol poly-unsaturated ethylenically presents 8-30 carbon atoms, preferably 15-25, especially 18-22 atoms of carbon. Some examples of fatty alcohols are alcohol oleyl, elaidyl alcohol, ricinolethyl alcohol, alcohol linoleilic, linolenyl alcohol, gadoleilic alcohol, alcohol erucilic or brasidyl alcohol, especially preferred ethylenically monounsaturated fatty alcohols.

The monomer unit b) preferably represents a hydrophilic monomer component, which should be taken into account as appropriate in the choice of the remains of the groups ester and amide. Possible carbon atoms in the remains of ester and / or amide groups are not yet included in the figure mentioned above of 2-8 carbon atoms. Preferably, the compound incorporating acid groups carboxylic, ester, amide or anhydride has a structure of hydrocarbon. With special preference, compounds with carboxylic acid and carboxylic acid anhydride groups. By example, maleic acid, fumaric acid, anhydride can be used maleic, itaconic acid or sorbic acid. It is also possible use a mixture of different monomer units b) for copolymer formation.

Although the monomer units a) and b) are found also as a copolymer block, or they can be statistically distributed in the copolymer, it is preferred that they form a copolymer alternating The molar relationship between the monomer units a) and b) in the copolymer depends on the iodine number and is calculated so that a correspondingly alternating copolymer is produced.

If the monomer unit a) comprises several different compounds of Formula I, these may also be distributed statistically in the copolymer or found alternating or as a block. According to the arrangement of the units monomers a) and b) in the copolymer, this means that in the case of its statistical distribution, a distribution can be presented completely statistical, in the case of monomer units a) and b) alternating, the different monomer units a) alternate statistically, they alternate as blocks or alternate orderly, while in the copolymer block, the unit block monomer a) can present a statistical distribution of different esters of phosphoric acid, as well as a distribution alternating or a block arrangement. Preferably used a mixture of a phosphoric acid monoester and an acid diester phosphoric, in which R 1 = R 2 in the diester, and in which the monomer units a) and b) alternate.

It is preferred that the copolymer be present as a salt Preferably the copolymer is used in the form of its alkaline salt, for example sodium salt or ammonium salt. They are also suitable organic derivatives from ammonium ion, present As counterions. So for example, it can be used monoethanolamine, diethanolamine, triethanolamine or monoisopropanolamine for salt formation.

The present invention also relates to a procedure for the preparation of the copolymers above mentioned, which comprises a radical polymerization of the components mentioned above a) and b) and then optionally, the reaction of the reaction product obtained with an alkaline solution However, it is also possible to preparation of the copolymers described above by others known copolymerization processes in the state of the technique.

Advantageously they are chosen as monomer units a) and b) compounds that do not polymerize with themselves. Preferably they are compounds of dicarboxylic acids or ethylenically monounsaturated anhydrides, such as maleic anhydride, maleic acid or itaconic acid. This has the advantage that, without need for other reaction control measures, there is a alternating copolymer and an excess of one of the monomers is enough to shift the reaction balance to the side of the copolymer.

The present invention also relates to a agent for the waterproofing of leather, which contains the copolymer described above. Surprisingly it has proven that the copolymers described confer on the leather a excellent waterproofing, which also remains high in the case of intense vegetable or synthetic retanning. Also in the case of completely chrome-free leather can be seen a Water absorption reduction. It is especially noteworthy the fact that the softness is not increased and that the leathers They have a tough character.

This was surprising in the sense that both phosphoric acid esters used for waterproofing that are known in the state of the art, as well as copolymers from carboxylic acids or acid anhydrides ethylenically unsaturated carboxylic and unsaturated hydrocarbons long chain, lead to a clear increase in softness, while on the contrary the present copolymer from the  phosphoric acid esters described and unsaturated compounds ethylenically they do not increase the softness and therefore are equally suitable for waterproofing leathers hard.

In a preferable embodiment, the leather treatment agent contains the copolymer described above in an amount of 10-60% in weight, preferably 15-50% by weight, with special preference of 20-30% by weight with respect to total agent

The present agent for the treatment of leather may additionally contain one or more substances of the group that understands

to)

fats, oils or waxes of origin natural or synthetic,

b)

emulsifiers, and

C)

silicone oils

Among the fats, oils or waxes used preferably, for example, hydrocarbons of long chain such as solid and / or liquid paraffin, chlorinated paraffins, paraffin oil or white oil, mineral oils and waxes paraffin. As for the synthetic compounds should be mentioned, for example alkylbenzenes, polyethylene waxes and waxes polyisobutyl. To suitable native oils and waxes wool fat, beeswax, carnauba wax belong, Fish oil, rapeseed oil and lecithin. They can also fatty acid esters are used here, such as oils of esters and polyol esters of fatty acids.

In the case of the emulsifiers used, it must keep in mind that these should not harm the waterproofing Therefore they are preferably chosen emulsifiers of the group of sarcosinates or sulphosuccinates.

Silicone oils optionally added to the present agent for the treatment of leather are preferably organically modified. With special preference they contain one or more amino and / or carboxyl groups.

Although the compounds mentioned above, when used without the copolymer according to the invention, they increase the softness of the waterproofed leather, it was surprisingly demonstrated that in combination with the copolymer described these compounds do not negatively influence the hardness of the leather. In particular, the combination of the copolymer with silicone oils and, very especially with organically modified silicone oils, as described above, it turned out, as for the waterproofing of intensely retanned leather vegetable or synthetic or chrome-free leathers, in an effect synergistic without decreasing the hardness of the leather, as would be expected Really.

In another preferred embodiment, the Leather treatment agent contains 0-30% by weight, preferably 5-20% by weight, with special preference 10-15% by weight of fats, oils or waxes of natural or synthetic origin; 0-30% by weight, preferably 10-25% by weight, with special preference 15-20% by weight of emulsifiers, in particular of the group consisting of sarcosinates or sulfosuccinates; and 0-25% by weight, preferably 5-20% by weight, with special preference 5-10% by weight of silicone oils, in particular aminofunctional silicone oils and / or with carboxyl groups functional.

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In addition, the present agent for treatment of the leather may contain up to 20% by weight of a solvent, per example glycols or glycol ethers such as hexylene glycol, butyl glycol, butyldiglycol, 1,2-propylene glycol, monoethylene glycol and other similar. In addition, the present agent for leather treatment optionally contains up to 80% in weight, preferably up to 60% by weight and preferably special up to 40% by weight of water.

Preferably the present agent for the Leather treatment has a pH value of 5.5-9.5, with special preference of 6-9 and with very special preference of 8-9. It has been shown that a Especially good solubility of the products in conditions basic.

Another object of the present invention relates to to a procedure for the treatment of leather, in which the leather treatment agent described above is employs at least one stage of treatment. Preferably, to In this regard, the leather treatment agent is used in a concentration of 1-20% by weight, with special preference of 2-15% by weight, with very special preference of 4-10% by weight with respect to at reduced weight. It is possible both to add the agent for the Leather treatment completely in one of the stages of wet finish, as well as distribute it in several stages of finishing, or in the case of one or several finishing stages divide the total amount in several portions and add them in moments different.

Although there is no limitation as to leather used, hard leather is preferably used, in particular one with a reduced thickness of 1.0-3.0 mm, preferably 2.0-2.7 mm.

The present invention is explained in more detail. in the following examples, but not limited by them. Yes the opposite is not indicated, the percentages refer to parts in weight compared to the weight of the lowered leather.

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Example one

In a round flask with agitator, condenser of reflux, gas inlet tube, drip funnel and control of temperature, 500 g of an oleyl phosphate are mixed (C 18 H 35 O) prepared according to the usual procedure, with an iodine number (according to Hanus) of approximately 80, with 156 g of maleic anhydride and the mixture is heated to 140 ° C with input of nitrogen. A drip funnel is continuously added a solution composed of 3 g of peroxide di-tert-butyl and 30 g of ether diethylene glycol monobutyl. The exotherm that occurs is a indication of the start of polymerization. The dosage of radical initiator is effected so that a temperature of approximately 160 ° C in the reaction flask. Depending on the case, it has to be subsequently regulated at the temperature indicated by heating or cooling At the end of the dosage (approximately 1 hour) a subsequent reaction of 3 takes place hours at 160 ° C. The viscous reaction product is cooled to 80 ° C and mix with 300 ml of water and 75 g of slowly added sodium solution (45%). For complete hydrolysis follow stirring for another 60 minutes at 70 ° C. The result is a golden yellow viscous product. Molar mass determination by means of gel permeation chromatography (GPC) it gave as result a mean molar mass Mw = 4300 Dalton.

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Example 2

The following composition is prepared:

20% polymer from Example 1

20% acid oleylsarcosinic

15% oil mineral

10% ether diethylene glycol monobutyl

5% oil amino functional silicone

30 of Water.

It is adjusted to pH 9 with monoethanolamine. It is a golden yellow oily liquid, which produces an emulsion with water finely divided.

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Example 3

In a round flask with agitator, condenser of reflux, gas inlet tube, drip funnel and control of temperature 500 g of a gadoleyl phosphate are mixed (C 20 H 39 O) prepared according to the usual procedure, with an iodine number (according to Hanus) of approximately 150, with 380 g of itaconic acid and the mixture is heated to 170 ° C with contribution of nitrogen. A drip funnel is continuously added a solution composed of 3 g of peroxide di-tert-butyl and 30 g of ether diethylene glycol monobutyl. The exotherm that occurs is a indication of the start of polymerization. The dosage of radical initiator is performed so that a temperature of approximately 170 ° C in the reaction flask. Depending on the case, it must subsequently adjusted to the temperature indicated by heating and / or cooling. At the end of the dosage (approximately 1 hour) a subsequent reaction of 3 takes place hours at 170 ° C. The viscous reaction product is cooled to 80 ° C and mix with 400 ml of water and slowly add 95 g of sodium solution (45%). For complete hydrolysis follow stirring for another 60 minutes at 80 ° C.

It is a brown viscous product. The Molar mass determination by means of GPC resulted in an average molar mass Mw = 5100 Dalton.

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Example 4

The following composition is prepared:

25% polymer from Example 3

20% acid lauryl arcosinic

10% oil mineral

10% oil silicone with functional carboxyl group

5 of butyl glycol

30 of Water.

It is adjusted to pH 8 with triethanolamine. It is a viscous brown and clear liquid that produces an emulsion of water thick dispersion

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Example 5

It is a cow leather in the "wet state" blue "with a reduced thickness of 2.0 to 2.2 mm according to the method next:

2

3

You get a very firm and hard grained leather which is suitable, for example, for military leather boots or for protective work shoes. The properties of waterproofing were determined according to DIN 53338, for that according to the thickness of the leather, a 10% emphasis was made.

Leather samples did not show permeation of water after 24 hours of the test, for a 13% water absorption.

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Example 6

It is a cow leather in the "wet state" blue "with a reduced thickness of 2.5 to 2.7 mm according to the method next:

4

5

You get a very firm and hard grained leather with a vegetal aspect. The waterproofing properties are checked according to ASTM D 2099 (Maeser test). The samples showed no water permeation after 50,000 pushups for a water absorption of 16%.

Claims (15)

1. A copolymer that can be obtained from monomer units comprising a) one or more compounds of formula 6 where R_ {1} represents H or a mono- or poly-unsaturated fatty alcohol ethylenically with 8 to 30 carbon atoms, preferably 15 to 25, or more preferably 18 to 22, and R2 represents the same or another mono- or poly-unsaturated fatty alcohol ethylenically with 8 to 30 carbon atoms, preferably 15 to 25, or more preferably 18 to 22, Y b) one or more linear chain compounds or branched, at least ethylenically monounsaturated, comprising 2 to 8 carbon atoms, and additionally, at least two groups carboxylic acid, ester or amide, or at least one anhydride group. 2. The copolymer according to claim 1, characterized in that the monomer unit b) is selected from the group consisting of maleic acid, fumaric acid, maleic anhydride, itaconic acid or sorbic acid. 3. The copolymer according to claim 1 or 2, characterized in that the monomer units a) and b) are alternately arranged in the copolymer. 4. The copolymer according to one of claims 1 to 3, characterized in that the copolymer is present in the form of a salt, in particular an alkaline salt or an ammonium salt. 5. Procedure for the preparation of copolymers according to one of claims 1 to 4, comprising a radical polymerization of components a) and b) of the claim 1, followed by an optional reaction of the product of reaction with an alkaline solution, ammonia or mono-, di- or tri-alkanolamine. 6. An agent for waterproofing the leather, which includes the copolymer according to one of the claims 1 to 4 7. The agent according to claim 6, characterized in that it incorporates the copolymer in amounts of 10 to 60% by weight, preferably 15 to 50% by weight and more preferably 20 to 30% by weight, relative to the total agent. The agent according to one of claims 6 or 7, characterized in that the agent additionally includes one or more substances within the group consisting of

a) fats, oils or waxes of natural or synthetic origin,

b) emulsifiers,

c) oils of silicone.

9. The agent according to claim 8, characterized in that the emulsifiers are selected from the group of sarcosinates or sulphosuccinates. 10. The agent according to one of claims 8 or 9, characterized in that the silicone oils are organically modified. 11. The agent according to claim 10, characterized in that the organically modified silicone oils include one or more amino and / or carboxyl groups. 12. The agent according to one of claims 6 to 11, characterized in that the agent has a pH value from 5.5 to 9.5. 13. A method for treating leather, characterized in that the leather treating agent according to one of claims 6 to 11 is used in at least one stage. 14. The method according to claim 13, characterized in that the leather treating agent is used in a concentration of 1 to 20% by weight in relation to the reduced weight. 15. The method according to one of claims 13 or 14, characterized in that hard leather is used, in particular leather with a reduced thickness of 1.0 to 3.0 mm.